1. Field of the Invention
This invention relates to an improved wick and to a liquid fuel combustion apparatus using the improved wick.
2. Description of the Prior Art
Liquid fuel combustion apparatus having burning wicks have been widely used, for example, as petroleum heaters or stoves. The existing wicks have drawbacks that when such heaters are used over a long period, tar-like or carbonaceous substances contained in the liquid fuel are gradually deposited and accumulated on the wick at the vaporizing or gasifying section or portion thereof. Accumulation of such substances make it difficult to allow smooth ignition of the heater and retard ability of the wick to ignite, impairing efficiency of combustion and causing the heater to operate in an unsatisfactory combustion state with harmful materials such as carbon monoxide being produced as residua in large amounts.
From a conservation standpoint, there is a recent trend to use a heavy oil as a liquid fuel. The use of heavy oil results in more accelerated accumulation of tar-like or carbonaceous residua causing the above-mentioned drawbacks become more considerable.
These drawbacks of prior art heaters are generally overcome by periodically subjecting a gasifying section of the burning wick to a blank burning where combustion is continued without supplying any fuel to the wick so as to remove the accumulated residua by combustion. However, since the gasifying section of existing burning wicks is ordinarily constituted of cotton fiber, staple fiber, or glass fiber assembled in a suitable form, these fibers may burn up or fuse during blank burning to such an extent that the wick is substantially unserviceable.